30% off all Honey Amp kits, check it out at https://store.ssguitar.com !
Started by joecool85, April 05, 2006, 07:37:26 PM
Quote from: rowdy_riemer on December 09, 2010, 02:53:27 PMHas anyone tried sand casting aluminum heatsinks? DIY aluminum sandcasting is supposed to be pretty easy.
Quote from: phatt on December 10, 2010, 03:36:40 AMSand Casting,, jeezz mate long gone :lmao:If you ever see how fast Ally comes out of an extrusion machine you will instanly see the folly of the idea.Casting Only used now for specialised applications.Trust JMF to try it,,, Somehow that does not suprise me as he has been known to try the impossible. :lmao:Re Fans,= Cheap crap in my opinion,,, If one cares to look at almost any industry a proper heat sink is not cheap and in this day Fans are proly 10 times cheaper that a heat sink.A fan might look trick but WILL ONE DAY STOP!!! Whereas a correctly designed heat sink will NEVER FAIL.Phil.
Quote from: J M Fahey on December 10, 2010, 12:11:26 AMWell, in fact I *did* something like that, back in the Stone Age.There were extruded heatsinks available, but fins run along the extrusion axis, and I needed transversal ones, to make my own vwersion of "big" US/Japan rack power amps, where they were used as the sides of the rack cabinets.*Huge* heatsinks !!!I made a wooden model, sandcast them, cleaned the very rough surface by airsanding (casting sand adheres to the surface) and last but not least, had to find a guy with a machine that mills aluminum engine blocks, I needed *one* surface quite flat to mount transistors.Truth is: a lot of work, and the engine block guy charged more for his work than al, the other costs put together. Not worth it.What I still do, is cut, bend and rivet 1/16" aluminum sheet, to build quite fancy heatsinks.That *is* cost effective.PC 12V fans have made the problem much smaller; any heatsink is 300/400% more efficient if blown cold air, and PC fans are very cheap and reliable.Sometimes I buy surplus CPU fans and heatsinks and bolt them to existing amps (think Bandits, Fender M80, etc.) which use the chassis as heatsink.
Quote from: rowdy_riemer on December 10, 2010, 09:20:58 AMIf only we all had extrusion machines. As silly as it might be, I might give sand casting a go. I've been looking for an excuse to sand cast something anyway. Well, I might only dream about it. School is eating up all my free time. Next week, I have to take a calc II final exam that is big enough that I have to show up on two different days to take it. Then, it'll be time for two more classes, including Calc III.If I ever do give it a go, I'll set up a power transistor whose only job is to get hot, and I'll try to measure it's effectiveness. If I can't get a flat enough surface for mounting, it'll no doubt get warmer than it should.